Cupola-furnace.



E. SGHijRMANN.

GUPOLA FURNACE.

APPLICATION FILED MAILB, 1913.

1,1 12,846. Patented Oct. 6, 1914.

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EDUABJD SCHURMANN, 0F KOETZSCHENBRODA, NEAR DRESDEN, GERMANY.

CUIOLA-FUBNACE.

Specification of Letters Patent.

Patented Oct. 6, 1914,

Application filed March 8, 1913. Serial No. 752,818.

To all whom it may concern Be it known that I, Eousno SGHI'J'RMANN,managing director, s subject of the King of Saxony, German Empire, andresident of illbertstrasse 5, lioetzschenbrodo, near Dresden, Saxony,German Empire,have invented new and useful improvements in Cupolalturneces, of which the following is a. specificetion.

It is s lrnown tact that in shaft-furnaces of any kind the carbonic acidformed in the so-called melting-zone will be reduced to carbonic onid,when passing or traversing the incandescent combustible above themelting-zone mentioned, said carbonic acid taking up carbon with e lossof heat. As the carbonic orrid gas is not used in melting orcalcining-furnaces in the same men'ner as for instence inblast-furnaces, it burns without any profit when leaving the chimney. lthes been tried to discharge or remove the cerbonic cold by openings,slots and pussages situated closely shove the melting-zone in the wellsoi the furnace. However only it very smell port of the carbonic acidformed was thus removed, whereas the greater part wes neverthelessdecomposed to carbonic oxid gee. The above mentioned openings, slotsendfpessages provided in the wells of the furnace have the drawback thntlerge quantities of the blast sitter heving left the blast-pipes ornozzles pass along the walls oi the furnace instead of entearing theinterior of the charge therein. it has else been tried to utilize thecarbonic ecid gas by sucking it through c. blast jetj end by blowing itfrom one side against the melting moss. But even this operation was notsuccessful for the reason that constantly new quantities of blast wereneeded end in consequence the greater part of-the gases "formed waswasted, and that, besides the heating of the melting moss toolr plece onor from one side only, thus excluding a uniform downward movement of thecharges.

The object of the present invention is to prevent the formation ofcarbonic oxi d eltogether. For this purpose the heetedblest is passedhorisontally and elternetely and,

in a transverse direction through the melt,- ing-zone, transforming thecarbon to carbonic acid. The letter passing off on the other side of thefurnace. and out of reach of carbon a. reduction to carbonic oxid ispractically prevented. The heat formed carried away from the meltingzoncby the blast is taken up and stored alternctel by regeneretors arrangedon both sides 0 the cuticle-furnace and also alternately utilized forpreliminarily heating the blast newly supplied. At the same time auniform downward movement of the charge is insured by the alternativeadmission of the heated blast. The fact that the blast admission anddischerge openings of the furnace face each other, makes it necessaryfor the air or blast current to positively penetrate the colre leyer ina transverse direction even if nozzles or openings of large diemeter areused. An upward movement of the combustible sses within the shaft of thefurnace will or y take place in a small measure, inasmuch as the shaftacts as e chimney. In thismennor the necessary preliminary heating ofthe charges within the shaft ofthe furnace is well insured. Theadmission and discharge of the blast on a common level odor also thetechnical advantage that the furnace shaft may be kept lower,furthermore that at considerable economy of combustible is obtained andthat the need of only one nozzle on each side simplifies the connectionwith the regcnerator. in this way the costs for such a melting-furneceplant as to its construction, operation and repairs are essentiallyreduced. The fact that the blast must pass transversely through thefurnace, allows a reduction of the high ressure now necessary to insurethat the b est will really penetrate into the center of the furnace.

In a. melting-furnace plant forming the object of the present inventionthe operation may take place with at low pressure, it only the necessaryquantity of blast is always at disposal. lherefore power may be saved.The low pressure mentioned is oi course also of advantage with regard tokeeping all sitating any mentor a suction-fan which may be preferable,for instance, if it is desired to further on utilize the heat stillpresent at the point in which the gases enter the draft-pipe or near thebutterfly-valve provided in such draft-pipe, or to make use of thecarbonic acid present in the'combustible or waste gases. The air willthen be admitted near the butterfly-valve mentioned Withoutnecesiteration or modification of the plant itsel? I A mode ofconstruction of the cupolamelting-furnace forming the object of thepresent invention is shown in the drawing annexed-herewith partly inlongitudinal section and partly in 'front elevation.

The two nozzles c 0 en into the furnace shaft 12 in the height 0 v thesmeltingzone a and areconnected by pipe-like air passages or channels (5with two hot blast apparatus or regenerators e. Both apparatus orregenera-tors e are connectedv one with another by a passage or channelZboth sides or ends of which ending in the upper walls or ceilings-ofsaid apparatus or regenerators. However the latter may be disconnectedone from another by the butterfly valve f in.-

serted into a connecting pipe 9-, the lower mouth 0t which is connectedto a fan or ventilator h whereas its upper mouth is connected to adischarge-pipe 2'.

In the position of the butterfly-valve f shown in the drawing theatmospheric air sucked in by the fan It passes or traverses the righthand hot blast apparatus 0, takes up heat and-circulates through theright hand channel (Z to the right hand nozzle 0 from which the heatedblast issues into the lower smelting-zone a maintained within theshaftof the furnace. When the hot blast or air hastraversed orcirculated through ,the smelting-zone in a horizontal ore nearlyhorizontal direction, the blast or air enters incth'e form of waste gasinto the left hand nozzle 0, passes the left hand channel or passage dand delivers its heat, received within the smelting-zone a, to theleft'hand hot blast apparatus or regenerator which hereafter is ready toreceive the atmospheric air circulating through the plant in an oppositedi' ection. The waste gases are, after their is re or discharge from theleft hand r flJitOI-G, directed along the butterfly cf to the chimney1', inthe direction shown in dotted lines. if s fter a certainlapse of.time the position of the butterfly-valve f is changedin-aknownmanner,the atmospheric air supplied by the fan or ventilator 7r circulatesthrough the leit hand regenerator in an opposite direction and entersthrough the left hand nozzle provided for the furnace-sheila into thesmeltin-gszone'jmain- The small siircharge or ever is reversed into itshorizontal position at the end of the melting operation, because whenthe column of the melting material within the furnace is reduced inheight, the blast will take the course of least resistance, viz: Itpasses through the melting-furnace itself in an upward direction and theair circulates through the shaft of the furnace.

' When the damper is is in its closed (horizon tal) position and thethrottle-valve f in its opened (also horizontal) position the air L mayenter into the furnace from both sides and the melting-operation may beterm-inated.

I claim as my invention:

1. A cupola furnace comprising a cylindrical body havin a meltingehamher providedwith ports 1n diametrically opposite positions, in themelting zone thereof, a

- stack rising from the said cylindrical body,

and devices for passing a heated blast through one of the said portsinto the said melting zone, causing the same. to pass through themelting zone in a substantially horizontal direction and the carbonicacid gas generated to be withdrawnthrongh the other port anddischargedindependently of the said stack so as to prevent the formationof carbonic onid within the melting ole-anther. i

2A cupol'a furnace comprising a cylindrical body having a meltingchamber provided with ports in diametrically opposite positions, inthemelting zone thereoflqa stack rising from the said cylindrical body,

"regenera/tors on both sides of the said cylindrical body, a pipeconnection between thecorresponding ends of the said regenerators, apipe connection between each 'regenerator and one of the said-ports,and: 'means for creating a blast and alternately directing the How ofthe same through one or the regenerators through the melting zone in ahorizontal path and withdrawing the resultant carbonic acid gas into andthrough the other regenerator and dis charging the same independentlyoi? the said stack.

'3. A cupola furnace comprising a c-ylindrical body having a meltingchamber pro-- vided with ports indiametrically opposite positions, inthe melting zonefthereof, a

regenerators on opposite sides of the said cylindrical body, pipeconnections from corresponding ends of the said regeneratorsto.

ilfy valve within the last aforesaid pipe, and

stack rising from the said cylindrical'body,

a. blower by which and the said butterfly In testimony, that I claim theforegoing valve blasts of air are created and alteras my invention, Ihave signed my name in 10 nately directed through one regenerator Eresence of two witnesses, this 17th day of through the said melting zonein a substanebruary 1913.

tially horizontal path and the resultant car- EDUARD SCHURMANN.

bonic acid gas withdrawn through the other Witnesses: regenerator anddischarged independently CLARE SIMON, of the said stack. PAUL ABRAS.

